1. Field of the Invention
The invention is directed to an improved unit for pumping fuel to an internal combustion engine.
2. Description of the Prior Art
German Patent DE 28 35 457 C2 discloses a roller cell pump in which a shaped sliding surface composed of elliptical portions results from two different equations. For various rotor diameters R2, the shaped sliding surfaces that can be generated from the equations are all mathematically similar with regard to the function of the unit, such as hot gasoline pumping, efficiency, and wear behavior, and are not optimal, and are inconstant at the transitions between the ellipse halves, for eccentricities not equal to one.